U.S. patent number 10,787,807 [Application Number 16/420,313] was granted by the patent office on 2020-09-29 for joint seal with multiple cover plate segments.
This patent grant is currently assigned to Schul International Co., LLC. The grantee listed for this patent is Schul International Co., LLC. Invention is credited to Steven R. Robinson.
United States Patent |
10,787,807 |
Robinson |
September 29, 2020 |
Joint seal with multiple cover plate segments
Abstract
A system creates a durable water-resistant seal in the joint
between adjacent panels. The durable expansion seal system includes
an elastically-compressive body, a first cover plate segment, a
second cover segment, and one or more ribs which provide a seal
against water when inserted between substrates and permitted to
expand to fit the gap between them.
Inventors: |
Robinson; Steven R. (Windham,
NH) |
Applicant: |
Name |
City |
State |
Country |
Type |
Schul International Co., LLC |
Pelham |
NH |
US |
|
|
Assignee: |
Schul International Co., LLC
(Pelham, NH)
|
Family
ID: |
1000004157095 |
Appl.
No.: |
16/420,313 |
Filed: |
May 23, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E04B
1/6803 (20130101); E04B 1/6812 (20130101); E04B
1/68 (20130101); E04B 1/6815 (20130101) |
Current International
Class: |
E04B
1/68 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Triggs; Andrew J
Attorney, Agent or Firm: Crain, Caton & James, P.C.
Hudson, III; James E.
Claims
I claim:
1. An expansion joint seal comprising: an elastically-compressive
body, the elastically compressive body having a body first side
surface, a body second side surface, a body centerline intermediate
the body first side surface and the body second side surface, a
body first side width from the body first side surface to the body
centerline, a body second side width from the body second side
surface to the body centerline, a body top surface extending from
the body first side surface to the body seconds side surface, a
body first end, a body second end, and a body longitudinal axis
from the body first end to the body second end; a first cover plate
segment above the elastically-compressible body, the first cover
plate segment adjacent the body top surface, the first cover plate
segment having a first cover plate segment first side surface
positioned between the body first side surface and the body
centerline, the first cover plate segment having a first cover
plate width greater than the body first side width, the first cover
plate segment extending beyond the body first side surface; a
second cover plate segment above the elastically-compressible body,
the second cover plate segment adjacent the body top surface, the
second cover plate segment having a second cover plate segment
first side surface positioned between the body second side surface
and the body centerline, the second cover plate segment having a
width greater than the body second side width, the second cover
plate segment extending beyond the body second side surface; a ribs
penetrating into the elastically-compressive body from above the
body top surface; the first cover plate segment fixed in relation
to the rib; and the second cover plate segment fixed in relation to
the rib.
2. The expansion joint seal of claim 1, wherein the first cover
plate segment and the second cover plate segment are connected to
the rib.
3. The expansion joint seal of claim 1, wherein the first cover
plate is affixed to a rubber seal at the first cover plate segment
first side surface and the second cover plate segment is affixed to
the rubber seal at the second cover plate segment first side
surface.
4. The expansion joint seal of claim 1, wherein the first cover
plate segment is affixed to a third member at the first cover plate
segment first side surface and the second cover plate segment is
affixed to the third member at the second cover plate segment first
side surface.
5. The expansion joint seal of claim 1, wherein the first cover
plate segment has a first cover plate segment front surface and the
second cover plate segment has a second cover plate segment rear
surface, the first cover plate segment and the second cover plate
segment are adjacent along the longitudinal axis, and the first
cover plate segment front surface and the second cover plate
segment rear surface are partially adjacent.
6. An expansion joint seal comprising: an elastically-compressive
body, the elastically compressive body having three body members
interspersed with two ribs, a body first side surface, a body
second side surface, a body centerline intermediate the body first
side surface and the body second side surface, a body first side
width from the body first side surface to the body centerline, a
body second side width from the body second side surface to the
body centerline, a body top surface extending from the body first
side surface to the body seconds side surface, a body first end, a
body second end, a body longitudinal axis from the body first end
to the body second end; a first cover plate segment above the
elastically-compressible body, the first cover plate segment
adjacent the body top surface, the first cover plate segment having
a first cover plate segment first side surface positioned between
the body first side surface and the body centerline, the first
cover plate segment having a first cover plate width greater than
the body first side width, the first cover plate segment extending
beyond the body first side surface; a second cover plate segment
above the elastically-compressible body, the second cover plate
segment adjacent the body top surface, the second cover plate
segment having a second cover plate segment first side surface
positioned between the body second side surface and the body
centerline, the second cover plate segment having a second cover
plate width greater than the body second side width, the second
cover plate segment extending beyond the body second side surface;
the first cover plate segment fixed in relation to a first of the
two ribs; and the second cover plate segment fixed in relation to a
second of the two ribs.
7. The expansion joint seal of claim 6, wherein the first cover
plate segment and the second cover plate segment are affixed to a
rubber seal.
8. The expansion joint seal of claim 6, wherein the first cover
plate segment and the second cover plate segment are connected to a
third member.
9. An expansion joint seal comprising: an elastically-compressive
body, the elastically compressive body having a body first side
surface, a body second side surface, a body centerline intermediate
the body first side surface and the body second side surface, a
body first side width from the body first side surface to the body
centerline, a body second side width from the body second side
surface to the body centerline, a body top surface extending from
the body first side surface to the body seconds side surface, a
body first end, a body second end, and a body longitudinal axis
from the body first end to the body second end; a first cover plate
segment above the elastically-compressible body, the first cover
plate segment adjacent the body top surface, the first cover plate
segment having a first cover plate segment first side surface
positioned between the body first side surface and the body
centerline, the first cover plate segment having a first cover
plate width greater than the body first side width, the first cover
plate segment extending beyond the body first side surface; a
second cover plate segment above the elastically-compressible body,
the second cover plate segment adjacent the body top surface, the
second cover plate segment having a second cover plate segment
first side surface positioned between the body second side surface
and the body centerline, the second cover plate segment having a
second cover plate segment width greater than the body second side
width, the second cover plate segment extending beyond the body
second side surface; a plurality of ribs penetrating into the
elastically-compressive body from above the body top surface; the
first cover plate segment fixed in relation to one of the plurality
of ribs; and the second cover plate segment fixed in relation to
another of the plurality of ribs.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
None.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
BACKGROUND
Field
The present disclosure relates generally to systems for creating a
durable water-resistant seal in the joint between adjacent panels.
More particularly, the present disclosure is directed to providing
a durable expansion seal system having an elastically-compressive
body, a first cover plate segment, a second cover segment, and one
or more ribs.
Description of the Related Art
Construction panels come in many different sizes and shapes and may
be used for various purposes, including roadways, sideways, tunnels
and other pre-cast structures. Where the construction panels are
concrete, it is necessary to form a lateral gap or joint between
adjacent panels to allow for independent movement, such in response
to ambient temperature variations within standard operating ranges.
These gaps are also used to permit moisture to be collected and
expelled. Cavity walls are common in masonry construction,
typically to allow for water or moisture to condense or accumulate
in the cavity or space between the two exterior walls. Collecting
and diverting moisture from the cavity wall construction can be
accomplished by numerous well-known systems. The cavity wall is
often ventilated, such as by brick vents, to allow air flow into
the cavity wall and to allow the escape of moisture heat or
humidity. In addition to thermal movement or seismic joints in
masonry walls, control joints are often added to allow for the
known dimensional changes in masonry over time. Curtain wall or
rain screen design is another common form of exterior cladding
similar to a masonry cavity wall. Curtain walls can be designed to
be primarily watertight but can also allow for the collection and
diversion of water to the exterior of the structure. A cavity wall
or curtain wall design cannot function as intended if the water or
moisture is allowed to accumulate or condense in the cavity wall or
behind a curtain wall or rain screen design cannot be diverted or
redirected back to the outside of the wall. If moisture is not
effectively removed it can cause damage ranging from aesthetic in
the form of white efflorescence buildup on surface to mold and
major structural damage from freeze/thaw cycling.
Thus, expansion and movement joints are a necessary part of all
areas of construction. The size and location of the movement
depends on variables such as the amount of anticipated thermal
expansion, load deflection and any expected seismic activity. Joint
movement in a structure can be cyclical in design as in an
expansion joint or in as a control joint to allow for the shrinkage
of building components or structural settling. These movement
joints serve an important function by allowing a properly designed
structure to move and the joint to cycle over time and to allow for
the expected dimensional changes without damaging the structure.
Expansion, control and movement joints are found throughout a
structure from the roof to the basement, and in transitions between
horizontal and vertical planes. It is an important function of
these expansion joints to not only move as intended but to remain
in place through their useful lifespan. This is often accomplished
by extending the length and/or width of the expansion joint system
over or past the edge of the gap or joint opening to attach to the
joint substrate or another building component. Examples of building
components that would ideal to integrally join an expansion joint
with and seal would be, although not limited to, waterproofing
membranes, air barrier systems, roofing systems and transitions
requiring the watertight diversion of rain water. Although these
joints represent only a small percentage of the building surface
area and initial cost, they often account for a large percentage of
waterproofing, heat loss, moisture/mold problems and other serious
interior and exterior damage during the life of the building.
Conventional joint sealants like gunnable sealants and most foam
seals are designed to hold the water out of the structure or
expansion joint. However, water can penetrate the joint substrate
in many ways such as cracks, poor sealant installation, roofing
details and a porous substrate or wall component. When water or
moisture enters the wall the normal sealing function of joint
sealant may undesirably retain the moisture in the wall. Foam joint
seals known in the art typically rely on the application of an
elastomer sealant on the primary or exposed face of foam to provide
the water-resistant function. Such joint seals are not waterproof
but retard the penetration of water into the joint by providing a
seal between adjacent substrates for a time and under a maximum
pressure. Particularly, such joint seals are not waterproof--they
do not preclude water penetration under all circumstances. While
this is helpful initially to keep water out of the joint and
structure it does not allow for this penetrating water or moisture
to escape.
Further complicating operation, some wall designs, such as cavity
walls, allow for moisture to enter a first wall layer where it
collects and is then directed to the outside of the building by
flashing and weep holes. In these systems, water can sometimes be
undesirably trapped in the cavity wall, such as at a mortar bridge
in the wall, or other impediment caused by poor flashing selection,
design or installation. When a cavity wall drainage system fails,
water is retained within the structure, leading to moisture
accumulating within in the wall, and to an efflorescence buildup on
the exterior of the wall. This can also result in freeze-thaw
damage, among other known problems.
To be effective in this environment, fully functional, foam-based
joint seals require a minimum compression ratio and impregnation
density. It is known that higher densities and ratios can provide
addition sealing benefits. Cost, however, also tends to increase
with overall density. There is ultimately a trade-off between
compression ratio/density range and reasonable movement
capabilities at about 750 kg/m.sup.3. As can be appreciated, this
compressed density is a product of the uncompressed density of the
material and the desired compression ratio to obtain other
benefits, such as water resistance. For example, a foam having an
uncompressed density of 150 kg/m.sup.3 uncompressed and compressed
at a 5:1 ratio results in a compressed density of 750 kg/m.sup.3.
Alternative uncompressed densities and compression ratios may reach
that compressed density of 750 kg/m.sup.3 while producing different
mechanical properties. It has been long known in the art that a
functional foam expansion joint sealant can be constructed using an
uncompressed impregnated foam density range of about 80 kg/m.sup.3
at a 5:1 compression ratio, resulting in a compressed density of
400 kg/m.sup.3. This functional foam expansion joint sealant is
capable of maintaining position within a joint and its profile
while accommodating thermal and seismic cycling, while providing
effective sealing, resiliency and recovery. Such joint seals are
not fireproof but retard the penetration of fire into the joint by
providing a seal which protects the adjacent substrates or the base
of the joint for a time and under a maximum temperature.
Particularly, such joint seals are not fireproof--they do not
preclude the burning and decomposition of the foam when exposed to
flame.
Another alternative known in the art for increasing performance is
to provide a water resistant impregnated foam at a density in the
range of 120-160 kg/m.sup.3, ideally at 150 kg/m.sup.3 for some
products, with a mean joint size compression ratio of about 3:1
with a compressed density in a range of about 400-450 kg/m.sup.3,
although densities in a broader range, such as 45-710 kg/m.sup.3
uncompressed and installed densities, after compression and
installation in the joint, of 45 kg/m.sup.3 and 1500 kg/m.sup.3 may
also be used. These criteria ensure excellent movement and cycling
while providing for fire resistance according to DIN 4112-2 F120,
meeting the Conditions of Allowance under UL 2079 for a two-hour
endurance, for conventional depth, without loading, with one or
more movement classifications, for a joint not greater than six
inches and having a movement rating as great as 100%, without a
hose stream test, and an ASTM E-84 test result with a Flame Spread
of 0 and a Smoke Index of 5. This density range is well known in
the art, whether it is achieved by lower impregnation density and
higher foam compression or higher impregnation density and a lower
compression ratio, as the average functional density required for
an impregnated open cell foam to provide sealing and other
functional properties while allowing for adequate joint movement up
to +/-50% or greater. Foams having a higher uncompressed density
may be used in conjunction with a lower compression ratio, but
resiliency may be sacrificed. As the compressed density increases,
the foam tends to retard water more effectively and provides an
improved seal against the adjacent substrates. Additives that
increase the hydrophobic properties or inexpensive fillers such as
calcium carbonate, silica or alumina hydroxide (ATH) provided in
the foam can likewise be provided in a greater density and become
more effective. Combustion modified foams such as a combustion
modified flexible polyurethane foam, combustion modified ether
(CME) foam, combustion modified high resilience (CMHR) foam or
combustion modified Viscoelastic foam (CMVE) can be utilized in the
preferred embodiments to add significant fire resistance to the
impregnated foam seal or expansion joint without adding additional
fire-retardant additives. Foam that is inherently fire resistant or
is modified when it manufactured to be combustion or fire-resistant
reduces the cost of adding and binding a fire retardant into the
foam. This method has been found to be advantageous in allowing
fire resistance in foam seals configured in very high compression
ratios such 5:1 and higher.
Current systems pre-compressed and compressible foam joint sealants
and expansion joints use relatively large volumes of foam and
silicone as part of their structure. It is known in the art that
some products are supplied as a foam sealant without an additional
coating with the functional features of the joint sealant system
are supplied by the type of foam that is used, the type of binder
and the type and quality of the additives in the impregnation
compound. These systems work by filling or coating a varying
percentage of the cells of the foam with the function filler by the
impregnation, partial impregnation, surface impregnation, coating
or by infusion such that they have varying degrees of
hydrophobicity. The type of foam, density, cell structure, pore
size, internal recovery force is known to vary depending the
desired properties and would be known to one skilled in the art.
Typical foams would polyether or polyester polyurethane foam but
other foams with special properties such as melamine or silicone
foams are advantageous for high fire-resistance. Higher quality
foam and functional additives such as fire-resistant compounds
increase the cost of the impregnation compound. Additionally, due
to the foam sealant providing all of the functional properties of
the system, higher compression ratios are often used to obtain
adequate performance. The higher the compression ratio the more of
the expensive foam and function binder and additives are used in
the product increasing the cost. It is known that these systems can
require a compression ratio from about 3:1 up to 8:1 from the
uncompressed foam dimension. It is therefore desirable to reduce
the ratio of the expensive functional foam and still provide the
same function and features. Examples uncoated pre-compressed
expanding foam joint sealants for movement joints are Sealtite by
Schul International which has the waterproofing, fire-resistance,
and UV stability provided by type and quality of the foam and the
additives to the sealant binder without the need for an additional
sealant or coating. This invention is not limited to precompressed
foam sealants and should be obvious to one skilled in the art it
would serve the same advantageous functions in a compressible foam
joint sealant supplied in an uncompressed or partially compressed
state.
It is known in the art to use a combination of a sealant and a foam
to provide a hybrid joint sealant or expansion joint system. A
representative product would be Seismic Sealtite II by Schul
International. It is common in these systems to use silicone or
other surface coating to provide some part of the functional
feature of the system such as water resistance, UV stability,
fire-resistance, chemical resistance, USDA/FDA allowance for food
contact, color although not limited to these functions. These
sealants or coatings typically add significant expense to these
hybrid systems component of the impregnated foam systems. It would
therefore be desirable to reduce the volume of surface coating
required while still providing its intended function. Silicone had
been found to be a preferred coating but the current invention is
not limited to silicone coatings and would alternatively include
hybrid gunnable sealants such as silicone-polyurethane, and other
construction sealants and coatings such as polyurethane,
polysulfide, acrylic, intumescent, fire-resistant, UV, mildew and
other coatings that would add a useful hybrid function to the
impregnated foam and known to those skilled in the art.
Further, conventional systems require the impregnated foam to be
either coated at full width requiring a relatively high number of
folds/bellows and a relatively higher compression ratio or
partially compressed usually requiring fixtures which is cumbersome
and time consuming and in a high compression ratio typically
greater than 3:1 and often much higher. Higher compression with
lower impregnation levels are known to allow for greater movement
capabilities. Alternatively, it would be advantageous to allow for
a higher level of functional fillers in a lower compression ratio
foam to achieve the movement range of a higher compression ratio of
foam and less functional filler. It is also recognized that the
more a foam is compressed, the greater the damage to the foam cell
structure, impacting the capability of the foam to recover.
Further, the higher compression ratios increase the rate at which
the primary surface coating of the foam would fatigue when bent
into a tight fold or bellows. It would therefore be desirable to
reduce the number of folds and the extent of compression during
operation. Alternatives to reduce silicone, the ribs, and the
extent of compression have been considered previously, but were
found to require undesirable amounts of labor and preparation
space. These have included, for example, partially compressing the
impregnated foam joint seal before applying the silicone coating.
It allows for high compression in a specific area of the foam
expansion joint sealant reducing the required amount of foam
impregnated with functional additives and sealant coating costs.
This novel invention reduces the amount of foam required and
eliminates the need for compression and coating fixture devices for
systems that are coated in partial compression. This system saves
time, space, labor, material while providing the same functionality
as a partially compressed and coated system.
By selecting the appropriate additional component, the type of
foam, the uncompressed foam density and the compression ratio, the
majority of the cell network will be sufficiently closed to impede
the flow of water into or through the compressed foam seal thereby
acting like a closed cell foam. Beneficially, an impregnated or
infused open cell foam can be supplied to the end user in a
pre-compressed state in rolls/reels or sticks that allows for an
extended release time sufficient to install it into the joint gap.
To further the sealing operation, additional components may be
included. For example, additives may be fully or partially
impregnated, infused or otherwise introduced into the foam such
that at least some portion of the foam cells are effectively
closed, or a hydrophobic or water-resistant coating is applied.
However, the availability of additional components may be
restricted by the type of foam selected. Closed cell foams which
are inherently impermeable for example, are often restricted to a
lower joint movement range such as +/-25% rather than the +/-50% of
open celled foams. Additionally, the use of closed cell foams
restricts the method by which any additive or fillers can be added
after manufacture. Functional features such as fire resistance to
the Cellulosic time-temperature curve for two hours or greater can
be however be achieved in a closed cell foam seal without impacting
the movement properties. Intumescent graphite powder added to a
polyethylene (PE), ethylene vinyl (EVA) acetate or other closed
cell foam during processing in a ratio of about 10% by weight has
been found to be a highly effective in providing flexible and
durable water- and fire-resistant foam seal. While intumescent
graphite is preferred, other fire retardants added during the
manufacture of the closed cell foam are anticipated and the ratio
of known fire retardants, added to the formulation prior to
creating the closed cell foam, is dependent on the required fire
resistance and type of fire retardant. Open celled foams, however,
present difficulties in providing water-resistance and typically
require impregnation, infusion or other methods for introducing
functional additives into the foam. The thickness of a foam core or
sheet, its resiliency, and its porosity directly affect the extent
of diffusion of the additive throughout the foam. The thicker the
foam core or sheet, the lower its resiliency, and the lower its
porosity, the greater the difficulty in introducing the additive.
Moreover, even with each of these at optimum, the additive will
likely not be equally distributed throughout the foam but will be
at increased density at the inner or outer portions depending on
the impregnation technique.
A known solution in the art is the use of foam segments bonded
together laterally to provide a lamination. However, such lateral
laminations can separate from one another, creating fissures and
openings for contaminates. Moreover, because the laminations are
laterally positioned, the resulting pressure exerted by the joint
seal against the adjacent substrates is a function of the combined
densities and thicknesses and is constant at all heights of the
substrate wall.
It is also known that the thin built-up lateral laminations must be
adhesively bonded to avoid separation, and therefore failure, under
thermal shock, rapid cycling or longitudinal shear. Because of the
cost to effectively bond the lateral laminations, a
cost/performance assessment sometimes produces laminations loosely
held together by the foam compression rather than by an adhesive.
While this is known in the art to be somewhat effective in low
performance applications and OEM assembly uses, it also known that
it cannot meet the demands of high movement seismic, shear,
deflection joints or where fail-safe performance is required. In
light of these issues, the preferred embodiment for a high movement
impregnated foam expansion joint has been found to instead be a
monolithic foam design comprised of a single impregnated foam core.
However, lamination systems are often still considered desirable
when the lamination adds a functional feature such as integrating a
water-resistant membrane, a fire-resistant layer or other
beneficial function.
Construction of lamination systems have typically been lateral
composites considered undesirable or inferior for a high movement
or rapid cycling fire resistant expansion joint sealant. The higher
compression ratios and greater volumes of fire-retardant additives
are likely to cause the foam to fatigue more rapidly and to lose
much of its internal recovery force. This proves problematic over
time due to the anticipated exposure to movement and cycling as the
impregnated foam will tend to lose its recovery force and rely more
on the push-pull connection to the joint substrate. When foam
laminations are vertically-oriented, the laminations can de-bond or
de-laminate and separate from one another, leading to only the
outer most lamination remaining attached to the joint substrate,
resulting in the laminated foam joint sealant ceasing to provide
either water, air or fire resistance.
A known alternative or functional supplement to the use of various
impregnation densities and compression ratios is the application of
functional surface coatings such as water-resistant elastomers or
fire-resistant intumescents, so that the impregnated foam merely
serves as a "resilient backer". Almost any physical property
available in a sealant or coating can be added to an already
impregnated foam sealant layering the functional sealant or coating
material. Examples would include but not limited to, fire ratings,
waterproofing, color, UV resistance, mold and mildew resistance,
soundproofing, impact resistance, load carrying capacity, faster or
slower expansion rates, insect resistance, conductivity, chemical
resistance, pick-resistance and others known to those skilled in
the art. For example, a sealant or coating having a rating or
listing for Underwriters Laboratories 2079 may be applied to an
impregnated compressed foam to create a fire-resistant foam
sealant.
One approach to addressing the shortcomings has been the creation
of composite materials, where the foam core--whether solid or
composed of laminations of the same or differing compositions--is
coated or surface impregnated with a functional layer, so that the
foam is merely a resilient backer for the sealant, intumescent or
coating, such that the composition and density become less
important. These coatings, and the associated properties, may be
adhered to the surface of each layer of a core or layered thereon
to provide multiple functional properties. As can be appreciated,
the composite material may have different coatings applied the
different sides to provide desired property or properties
consistent with its position. Functional coatings such as a
water-resistant sealant can protect the foam core from absorbing
moisture even if the foam or foam impregnation is hydrophilic.
Similarly, a functional coating such as a fire-rated sealant added
to the foam core or lamination with protect a foam or foam
impregnation that is flammable. A biocide may even be included.
This could be layered, or on opposing surfaces, or--in the case of
a laminate body--on perpendicular surfaces.
Additionally, it has become desirable, and in some situations
required, for the joint sealant system to provide not only water
resistance, but also fire resistance. A high degree of fire
resistance in foams and impregnated foam sealants is well known in
the art and has been a building code requirement for foam expansion
joints in Europe for more than a decade. Fire ratings such as UL
2079, DIN 4112-2, BS 476, EN1399, AS1503.4 have been used to assess
performance of expansion joint seals, as have other fire resistance
tests and building codes and as the basis for further fire
resistance assessments, the DIN 4112 standard, for example, is
incorporated into the DIN 18542 standard for "Sealing of outside
wall joints with impregnated sealing tapes made of cellular
plastics--Impregnated sealing tapes". While each testing regime
utilizes its own requirements for specimen preparation and tests
(water test, hose stream tests, cycling tests), the 1998 version of
UL 2079, the ISO 834, BS 476: Part 20, DIN 4112, and AS 1530.4-1995
use the Cellulosic time/temperature curve, based on the burning
rate of materials found in general building materials and contents,
which can be described by the equation T=20+345*LOG(8*t+1), where t
is time in minutes and T is temperature in C. While differing
somewhat, each of these testing regimes addresses cycling and water
resistance, as these are inherent in a fire-resistant expansion
joint. The fire resistance of a foam sealant or expansion has been
sometimes partially or fully met by infusing, impregnating or
otherwise putting into the foam a liquid-based fire retardant, such
as aluminum tri-hydrate or other fire retardants commonly used to
add fire resistance to foam. Unfortunately, this increases weight,
alters the foam's compressibility, and may not provide the desired
result without additional fire-resistant coatings or additives if a
binder, such as acrylic or polyurethane, is selected to treat the
foam for fire and water resistance. Doing so while maintaining
movement properties may affect the foam's compressibility at
densities greater than 750 kg/m.sup.3. Ultimately, these specialty
impregnates and infused compositions increase product cost.
It has further become desirable or functionally required to apply a
fire-resistant coating to the foam joint systems to increase fire
and water resistance, but often at the sacrifice of movement.
Historically, fire-resistant foam sealant products that use an
additional fire-resistant surface coating to obtain the life safety
fire properties have been limited to only +/-25% movement
capability, especially when required to meet longer
time-temperature requirements such as UL2079's 2 hour or longer
testing. This +/-25% movement range is too limited for most
movement joints and would not meet most seismic movement and
expansion joint requirements. One well-known method for utilizing
these low movement fire resistant joint sealants is to increase the
width or size of the joint opening, an undesirable and expensive
alternative, to allow for a commonly required +/-50% joint movement
rating.
Unfortunately, supplying a pre-coated foam seal from the factory
requires long leads times due to the required curing time, which
can often hold up completion of projects in the final stages. This
shortcoming is exacerbated if the composite material requires an
additional functional layer to provide the desired properties.
Installing the foam seal and adding another sealant in the field
eliminates the one-step advantage of pre-compressed foam seals. The
required multi-step process is labor and skill intensive and
becomes even more challenging when the joint becomes greater than
one inch, which pose difficulties for installation and to provide
an aesthetically pleasing finished joint seal.
In certain circumstances, the expansion joint seal design must
accommodate situations requiring the support of transfer loads have
often required the use of rigid extruded rubber or polymer glands.
These systems lack the resiliency and seismic movement required in
expansion joints. These systems have been further limited in
functioning as a fire-resistant barrier, which is often a desired
function.
Other systems have incorporated cover plates that span the joint
itself, often anchored to the concrete or attached to the expansion
joint material and which are expensive to supply and install. These
systems sometimes require potentially undesirable mechanical
attachment, which requires drilling into the deck or joint
substrate. Cover plate systems that are not mechanically attached
rely on support or attachment to the expansion joint, thereby
subjecting the expansion joint seal system to continuous
compression, expansion and tension on the bond line when force is
applied to the cover plate, which shortens the life of the joint
seal system. Some of these systems use foam to provide sealing. But
these foam systems can take on a compression set when the joint
seal system is repeatedly exposed to lateral forces from a single
direction, such as a roadway. This becomes more pronounced as these
foam systems utilize a single or continuous spine along the length
of the expansion joint seal system--which propagates any deflection
along the length. The problems and limitations of the current foam
sealing cover plate systems that rely on a continuous spline are
well known in the art.
These cover plate systems are designed to address lateral
movement--the expansion and compression of adjacent panels.
Unfortunately, these do no properly address vertical shifts--where
the substrates become misaligned when the end of one shifts
vertically relative to the other. In such situations, the
components attached to the cover plate are likewise rotated in
space causing a pedestrian or vehicular hazard. The inability of
the current art to compensate for the lateral or thermal movement
of the cover plate results in failure of attachment to the cover
plate or additional pressure being imposed on one half of the
expansion joint system and potentially pulling the expansion joint
system away from the lower substrate.
It would be an improvement to the art to provide an expansion joint
seal incorporating a multicomponent cover plate and associated rib
which maintains flexibility while providing impermeability,
particularly where the compressibility, density, and spring force
may vary across the entirety of the expansion joint seal.
SUMMARY
The present disclosure therefore meets the above needs and
overcomes one or more deficiencies in the prior art. An expansion
joint seal is provided which includes an elastically-compressive
body, a first cover plate segment, a second cover plate segment,
and at least one rib. The elastically compressive body has a body
first side surface, a body second side surface, a body centerline
intermediate the body first side surface and the body second side
surface, a body first side width from the body first side surface
to the body centerline, a body second side width from the body
second side surface to the body centerline, a body top surface
extending from the body first side surface to the body seconds side
surface, a body first end, a body second end, and a body
longitudinal axis from the body first end to a body second. The
first cover plate segment is positioned above the
elastically-compressible body and adjacent the body top surface and
has a first cover plate segment first side surface positioned
between the body first side surface and the body centerline. The
first cover plate segment has a first cover plate width greater
than the body first side width and extends beyond the body first
side surface. The second cover plate segment is positioned above
the elastically-compressible body and is adjacent the body top
surface. The second cover plate segment has a second cover plate
segment first side surface positioned between the body second side
surface and the body centerline, a width greater than the body
second side width, and extends beyond the body second side surface.
One or more ribs penetrate into the elastically-compressive body
from above the body top surface and therefore provide a point of
connection between the first cover segment, the second cover
segment and the elastically-compressive body. The first cover
segment is therefore fixed in relation to the one or more ribs and
the second cover segment is likewise fixed in relation to the one
or more ribs.
Additional aspects, advantages, and embodiments of the disclosure
will become apparent to those skilled in the art from the following
description of the various embodiments and related drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the described features, advantages, and
objects of the disclosure, as well as others which will become
apparent, are attained and can be understood in detail; more
particular description of the disclosure briefly summarized above
may be had by referring to the embodiments thereof that are
illustrated in the drawings, which drawings form a part of this
specification. It is to be noted, however, that the appended
drawings illustrate only typical preferred embodiments of the
disclosure and are therefore not to be considered limiting of its
scope as the disclosure may admit to other equally effective
embodiments.
In the drawings:
FIG. 1 illustrates an end view of the present disclosure.
FIG. 2 illustrates a top view of the present disclosure.
FIG. 3 illustrates an end view of a further embodiment of the
present disclosure.
FIG. 4 illustrates an end view of another embodiment of the present
disclosure.
FIG. 5 illustrates an alternative embodiment of the present
disclosure.
FIG. 6 illustrates a top view of an additional alternative
embodiment is illustrated.
FIG. 7 illustrates an end view of the present disclosure with
packaging bodies.
FIG. 8 illustrates an isometric view of the rear of a packaging
body.
FIG. 9 illustrates an alternative further embodiment of the present
disclosure.
DETAILED DESCRIPTION
The present disclosure provides a durable expansion joint seal
which includes an elastically-compressive body, a first cover plate
segment, a second cover segment, and one or more ribs which provide
a seal against water when inserted between substrates and permitted
to expand to fit the gap between them.
Referring to FIG. 1, an end view of the present disclosure is
provided. The expansion joint seal 100 includes an
elastically-compressive body 102, a first cover plate segment 118,
a second cover plate segment 124, and one or more ribs 128.
Referring to FIG. 1, and FIG. 2, which discloses a top view of the
expansion joint seal 100, the expansion join seal 100 is disclosed.
The elastically-compressive body 102 has a body first side surface
104, a body second side surface 106, a body centerline 108
intermediate the body first side surface 104 and the body second
side surface 106, a body first side width 110 from the body first
side surface 104 to the body centerline 108, a body second side
width 112 from the body second side surface 106 to the body
centerline 108, a body top surface 114 extending from the body
first side surface 104 to the body seconds side surface 106, a body
first end 116, a body second end 204, a body longitudinal axis 202
from the body first end 116 to a body second 204. The first cover
plate segment 118 is positioned above the elastically-compressible
body 102 and is adjacent the body top surface 114. The first cover
plate segment 118 has a first cover plate segment first side
surface 120 positioned between the body first side surface 104 and
the body centerline 108. The first cover plate segment 118 further
has a first cover plate width 122 greater than the body first side
width 110 and extends beyond the body first side surface 104. The
second cover plate segment 124 is positioned above the
elastically-compressible body 102 and adjacent the body top surface
114. The second cover plate segment 124 has a second cover plate
segment first side surface 126 positioned between the body second
side surface 106 and the body centerline 108. The second cover
plate segment 124 further has a width greater than the body second
side width 112 and extends beyond the body second side surface 106.
Notably, neither of the first cover plate segment cover 118 nor the
second cover plate segment cover 124 spans the entirety of the
elastically-compressible body 102. The one or more ribs 128
penetrate into the elastically-compressive body from above the body
top surface. The first cover segment 118 is fixed in relation to
the one or more ribs 128 and the second cover segment 124 fixed in
relation to the one or more ribs 128. The first cover plate segment
cover 118 and the second cover plate segment cover 124 in this
embodiment are attached to the same rib 128. The first cover plate
segment first side surface 120 may abut the second cover plate
segment 124. Referring to FIG. 3, an end view of a further
embodiment of the present disclosure, and FIG. 4, an end view of
another embodiment of the present disclosure, when desired, the
first cover segment 118 and the second cover segment 124 may be
connected to the same one of the one or more ribs 128 or may be
affixed to a rubber seal 302 or to a member 402. When desired, the
one or more ribs 128 may be attached to the associated first cover
segment 118 and second cover segment 124 by a tether 130, 132. The
tether 130, 132, may be selected from available materials, and may
include plastic fibers, polypropylene rope, or metal ribbons, among
others. The tethers 130, 132 may be selected to fail upon
application of a maximum force, ensuring that a strike, such as by
a plow, will cause the first cover segment 118 and/or second cover
segment 124 to rip away, but leave the balance of the joint seal
intact. Alternatively, each of the first cover segment 118 and
second cover segment 124 may be connection directly to a rib, which
may be the same rib, by a flexible or hinged connection to permit
movement of each relative to the elastically-compressive body
102.
The elastically-compressive body 102 may be selected of a
resiliently-compressible material or composite and may be
lamination which includes laminates of materials which have
differing compressibilities or even may include a layer which is
incompressible. The elastically-compressive body 102 presents a
generally rectangular shape, but may be a hexagon, octogon, or more
complex shape. The shapes may be regular or irregular.
Referring to FIG. 6, a top view of an additional alternative
embodiment is illustrated. The first cover segment 618 may have a
first cover segment front surface 602 and the second cover segment
624 may have a second cover segment rear surface 604, where the
first cover segment 618 and the second cover segment 624 are
adjacent along the longitudinal axis, and the first cover segment
front surface 602 and the second cover segment rear surface 604 may
be partially adjacent.
In use, the joint seal 100 is positioned between substrates in
compression and maintains compression to seal against external
solids and liquids. To enable installation of the joint seal 100
between the substrates, the joint seal 100 is compressed below the
joint size. During operation, the joint seal 100 is often in
compression at one-third to one-sixth its original size. A greater
compression for delivery permits the product to be removed from
packaging and installed before the joint seal 100 relaxes to a
width greater than the expansion joint gap size between substrate
walls.
Because the joint seal 100 is in compression between the substrates
of an expansion joint, it is well-known to pre-compress the joint
seal 100 at the factory and provide the joint seal 100 in
compression. To prepare the joint seal 100 for delivery, it is
often desirable to compress the joint seal 100 to an even smaller
portion of its original size and then to include one or more
packaging members to provide rigidity and/or non-stick surface
against the surrounding packaging, such as shrink wrap.
Referring to FIG. 7, an end view of a joint seal 100 with two
packaging bodies 702, 704 is illustrated prior to compression. The
packaging body 702, 704 may be a board of any durable material,
including wood and plastic, or may be a thin plastic liner. The
first packaging body 702 has a first packaging body height 706, and
a first packaging body first surface 708. The first packaging body
height 706 is preferably equal to, though it may be greater or less
than, the elastically-compressive body height 134. The first
packaging body first surface 708 is adapted to contact the body
first side surface 104. The second packaging body 704 has a second
packaging body height 710 and a second packaging body first surface
712. The second packaging body height 710 is preferably equal to,
though it may be greater or less than, the elastically-compressive
body height 134. The packaging body 702, 704 may be provided with a
surface facing the elastically-compressive body 102 which deters
adhesion to facilitate later removal from the packaging for
installation between substrates.
Referring to FIG. 8, an isometric view of the rear of a first
packaging body 702 is provided. The first packaging body 702
includes a packaging body first surface 808 and has a packaging
body rear surface 802. The first packaging body 702 may be a
rectangular prism as illustrated in FIGS. 7 and 8 or may, when
desired, be of a different shape. For example, the first packaging
body 702 may have a conic or cylindrical shape, which may be
beneficial in reducing areas of stress concentration in any
tensioned packaging, such as shrink wrap.
The joint seal 100 is provided for installation in compression. The
first packaging body 702, any second packaging body 704, and the
various bodies are laterally compressed, to the extent each is
compressible. The joint seal 100 is then packaged, such as in
shrink wrap, to remain in compression. After the first packaging
body 702, and any second packaging body 704, is removed, the joint
seal 100 is imposed between the first substrate and the second
substrate before relaxing to a width greater than the expansion
joint. The joint seal 100 continues to relax and contacts the
substrate walls and is maintained in compression in the joint, and,
by virtue of its nature, inhibits the transmission of water or
other contaminants further into the expansion joint. The joint seal
100 may be adhered to the substrate walls by an adhesive on the
sides of the core bodies. When desired a second packaging body may
be provided on the opposing side of the joint seal 100.
The elastically-compressive body 102 may be a foam member or may be
a non-foam material which exhibits properties of compressibility,
expansion, resiliency, and to support liquid-based additives, such
a fire retardants and fillers. These may be a core, such as rubber
or cellulose or other material, or may be composed of a foam, such
as an open-celled polyurethane foam. These may have an overall
length sufficient for use on site, eliminating any need for a
splice to join to an adjacent joint seal 100. The joint seal 100 is
sized to fit between two panels or substrates and may be adjusted
in width and height to accommodate the intended lateral movement
and provide sufficient benefits.
When the elastically-compressive body 102 is to be constructed of
foam, any of various types of foam known in the art may be,
including compositions such as polyurethane and polystyrene, and
may be open or closed cell. The uncompressed density of the
elastically-compressive body 102 may also be altered for
performance, depending on local weather conditions. The density of
the elastically-compressive body 102 when relaxed and prior to any
compression may be less 400 kg/m.sup.3. The composition of the
elastically-compressive body 102 may be selected of a composition
which is fire retardant or water resistant.
The elastically-compressive body 102 may be a foam, such as an open
cell foam, a lamination of open cell foam and closed cell foam, and
closed cell foam. When desired, the elastically-compressive body
102 may have a treatment, such as impregnation, to increase
desirable properties, such as fire resistance or water resistance,
by, respectively, the introduction of a fire retardant into the
foam or the introduction of a water inhibitor into the foam.
Further, a the elastically-compressive body 102 may be composed of
a hydrophilic material, a hydrophobic material, a fire-retardant
material, or a sintering material.
The elastically-compressive body 102 may be formed of commercially
available vapor permeable foam products or by forming specialty
foams. Commercial available products which provide vapor permeable
and excellent fire-resistant properties are well known, such as
Sealtite VP or Willseal 600. It is well known that a
vapor-permeable but water-resistant foam joint sealant may be
produced leaving at least a portion of the cell structure open
while in compression such that water vapor can escape through the
impregnated foam sealant. Water is then ejected on the exterior of
the joint seal 100 because the foam, and/or any impregnation, is
hydrophobic and therefore repels water. Water can escape from the
foam sealant or wall cavity through water vapor pressure by virtue
of the difference in humidity creating unequal pressure between the
two areas. Because the cell structure is still partially open the
vapor pressure drive is sufficient to allow moisture to return to
equalization or the exterior of the structure. By a combination of
compression ratio and impregnation density of a hydrophobic
component the water resistance capacity can be increased to provide
resistance to various levels of pressure or driving rain.
Moreover, the material for the elastically-compressive body 102 may
be selected from partially closed cell or viscoelastic foams. Most
prior art foams seals have been designed as "soft foam"
pre-compressed foam seals utilizing low to medium density foam
about 16-30 kg/m3 and softer foam ILD range of about 10-20. It has
been surprisingly found through extensive testing of variations of
foam densities and foam hardness, fillers and elastic impregnation
compounds that higher density "hard" foams with high ILD's can
provide an effective foam seal meeting the required waterproofing
600 Pa minimum and ideally 1000 Pa or greater and movement and
cycling requirements such as ASTM E-1399 Standard Test Method for
Cyclic Movement and Measuring the Minimum and Maximum Joint Widths
of Architectural Joint Systems as well as long term joint cycling
testing. An advantage has been found in using higher density and
higher hardness higher ILD foams particularly in horizontal
applications. While at first this might seem obvious it is known in
the art that higher density foams that are about 32-50 kg/m3 with
an ILD rating of about 40 and greater tend to have other
undesirable properties such as a long term decrease in fatigue
resistance. Desirable properties such as elongation, ability to
resist compression set, foam resiliency and fatigue resistance
typically decline relative to an increase in density and ILD. These
undesirable characteristics are often more pronounced when fillers
such as calcium carbonate, melamine and others are utilized to
increase the foam density yet the cost advantage of the filled foam
is beneficial and desirable. Similarly, when graft polyols are used
in the manufacture of the base foam to increase the hardness or
load carrying capabilities, other desirable characteristics of the
base foam such as resiliency and resistance to compression set can
be diminished. Through the testing of non-conventional impregnation
binders and elastomers for pre-compressed foam sealants such as
silicones, urethanes, polyureas, epoxies, and the like, it has been
found that materials that have reduced tack or adhesive properties
after cure and which provide a high internal recovery force can be
used to counteract the long-term fatigue resistance of the high
density, high ILD foams. Further, it has been found that by first
impregnating and curing the foam with the injected or impregnated
silicone, acrylic, urethane or other low tack polymers and,
ideally, elastomers with about 100-199% elongation or greater
providing a sufficient internal recovery force, that it was
additionally advantageous to re-impregnate the foam with another
elastomer or binder to provide a timed expansion recovery at
specific temperatures. The impregnation materials with higher
long-term recovery capabilities imparted to the high density, high
ILD base foams, such as a silicone or urethane elastomers, can be
used to impart color to the foam seal or be a clear or translucent
color to retain the base foam color. If desirable a second
impregnation, partial impregnation or coating can be applied to or
into the foam seal to add additional functional characteristics
such as UV stability, mold and mildew resistance, color,
fire-resistance or fire-ratings or other properties deemed
desirable to functionality to the foam.
Viscoelastic foams have not typically been commercially available
or used for foam seals due to perceived shortcomings. Commonly used
formulations, ratios and methods do not provide a commercially
viable foam seal using viscoelastic foam when compared to standard
polyurethane foams. Open cell viscoelastic foams are more expensive
than polyester or polyether polyurethane foams commonly used in
foam seals. Any impregnation process on a viscoelastic foam tends
to proceed slower than on a traditional foam due to the fine cell
structure of viscoelastic foam. This can be particularly
frustrating as the impregnation materials and the impregnation
process are typically the most expensive component of a foam seal.
However, because of their higher initial density viscoelastic foams
can provide better load carrying or pressure resistant foam seal.
Both properties are desirable but not fully provided for in the
current art for use in applications such as load carrying
horizontal joints or expansion joints for secondary containment.
Common densities found in viscoelastic foams are 64-80 kg/m.sup.3
or greater. Additionally, viscoelastic foams have four functional
properties density, ILD rating, temperature and time compared to
flexible polyurethane foams, which have two primary properties
density and an ILD rating.
However, the speed of recovery of viscoelastic foams following
compression may be increased by reducing or eliminating any
impregnation, surface impregnation or low adhesive strength
impregnation compound. Incorporating fillers into the impregnation
compound is known to be effective in controlling the adhesive
strength of the impregnation binder and therefore the re-expansion
rate of the impregnated foam. By surface impregnating or coating
the outside surface of one or both sides of viscoelastic foam to
approximately 10% of the foam thickness, such as about 3-8 mm deep
for conventional joint seals, the release time can be controlled
and predicted based on ambient temperature. Alternatively, the foam
can be infused, partially impregnated or impregnated with a
functional or non-functional filler without a using binder but
rather only a solvent or water as the impregnation carrier where
the carrier evaporates leaving only the filler in the foam.
The re-expansion rate of a seal using viscoelastic foam may be
controlled by using un-impregnated viscoelastic foam strips and
re-adhering them with a pressure sensitive adhesive or hot melt
adhesive. When the seal is compressed, the laminating adhesive
serves as a temporary restriction to re-expansion allowing time to
install the foam seal. Viscoelastic foam may be advantageously
used, rather than standard polyurethane foam, for joints requiring
additional softness and flexibility due to higher foam seal
compression in hot climates or exposure or increased stiffness in
cold temperatures when a foam seal is at its minimum compressed
density. Additionally, closed cell, partially closed cell and other
foams can be used as in combination with the viscoelastic foams to
reduce the overall cost.
This second group of body materials, the non-foam members, may
include, for example, corrugated cardboards, natural and man-made
batting materials, and natural, synthetic and man-made sponge
material. When desired, such materials may be selected for
properties, such as water leakage, air leakage, resilience in face
of one or more cycling regimes, compressibility, relaxation rate,
compression set, and elasticity.
The material for the elastically-compressive body 102 may be
altered to provide additional functional characteristics. It may be
infused, impregnated, partially impregnated or coated with an
impregnation material or binder that is designed specifically to
provide state of the art seal water-resistance properties with a
uniform and consistent distribution of the waterproofing binder.
The elastically-compressive body 102 may also, or alternatively, be
infused or impregnated or otherwise altered to retain a fire
retardant, dependent on function. Where the elastically-compressive
body 102 is foam, any suitable open cell foam type with a density
of 16-45 kg/m.sup.3 or higher can provide an effective
water-resistant foam-based seal by varying the impregnation density
or the final compression ratio. Where a sound resistant seal is
desired, the density or the variable densities provide a sound
resistant seal in a similarly-rated wall from a Sound Transmission
Class value from 42-63 and/or a sound reduction between 12 and 50
decibels.
The elastically-compressive body 102 may be selected from an
inherently hydrophilic material or have a hydrophilic component
such as a hydrophilic polymer that is uniformly distributed
throughout. The elastically-compressive body 102 may include
strategically-placed surface impregnation or partially impregnate
with a hydroactive polymer. Because the primary function of the
joint seal 100 is waterproofing, the addition of a hydrophilic
function does not negatively impact any desired fire-resistant
properties, as an increased moisture content, and may increase fire
resistive properties.
Other variations may be employed. The joint seal 100 may be
constructed to withstand a hydrostatic pressure equal to or greater
than 29.39 psi. Environmentally friendly foam, fillers, binders,
elastomer and other components may be selected to meet
environmental, green and energy efficiency standards. The
elastically-compressive body 102 may exhibit auxetic properties to
provide support or stability for the joint seal 100 as it thermally
cycles or to provide additional transfer loading capacity. Auxetic
properties may be provided by the material selected for the
elastically-compressible body 102, the internal components such as
the members/membrane or by an external mechanical mechanism.
The elastically-compressive body 102 may include an impregnate,
such as a fire retardant such as aluminum trihydroxide, which may
be throughout its entirety or which may be only about ten percent
of it from one surface to the opposing surface. Additional function
properties can be added by surface impregnating the exposed or
outside surfaces of the foam as well as the inside portion if
additional properties are desirable. The elastically-compressive
body 102 may contain, such as by impregnation or infusion, a
sintering material, wherein the particles in the impregnate move
past one another with minimal effort at ambient temperature but
form a solid upon heating. Once such sintering material is clay or
a nano-clay. Such a sintering impregnate would provide an increased
overall insulation value and permit a lower density at installation
than conventional foams while still having a fire endurance
capacity of at least one hour, such as in connection with the UL
2079 standard for horizontal and vertical joints. While the cell
structure, particularly, but not solely, when compressed, of the
elastically-compressive body 102, preferably inhibits the flow of
water, the presence of an inhibitant or a fire retardant may prove
additionally beneficial. The fire retardant may be introduced as
part of the foaming process, or by impregnating, coating, infusing,
or laminating, or by other processes known in the art. The joint
seal 100 may be provided with end profiles intended to provide
interlocking faces so a plurality of joint seal 100 may be
installed in abutment.
Referring to FIG. 5, an alternative embodiment of the present
disclosure is provided. When desired, the expansion joint seal 100
may include an elastically-compressive body 102, a first cover
plate segment 118, and a second cover plate segment 124. The
elastically compressive body 102 has three body members 502a, 502b,
502c interspersed with two ribs 128a, 128b, a body first side
surface 104, a body second side surface 106, a body centerline 108
intermediate the body first side surface 104 and the body second
side surface 106, a body first side width 110 from the body first
side surface 104 to the body centerline 108, a body second side
width 112 from the body second side surface 106 to the body
centerline 108, a body top surface 114 extending from the body
first side surface 104 to the body seconds side surface 106, a body
first end 116, a body second end 204, and a body longitudinal axis
202 from the body first end 116 to a body second 204. The first
cover plate segment 118 is positioned above the
elastically-compressible body 102 and is adjacent the body top
surface 114. The first cover plate segment 118 has a first cover
plate segment first side surface 120 positioned between the body
first side surface 104 and the body centerline 108, a first cover
plate width 122 greater than the body first side width 110, and
extends beyond the body first side surface 104. The second cover
plate segment 124 is positioned above the elastically-compressible
body 102 and is adjacent the body top surface 114 and has a second
cover plate segment first side surface 126 positioned between the
body second side surface 106 and the body centerline 108, a width
greater than the body second side width 112, and extends beyond the
body second side surface 106. The first cover segment 118 fixed in
relation to a first of the two ribs 128a while the second cover
segment 124 fixed in relation to a second of the two ribs 128b.
Referring to FIG. 3, the first cover segment 118 and the second
cover segment 124 may each be affixed to a rubber seal 302 or to a
third member 402.
Referring to FIGS. 1 and 5, a coating 136, 504 may be applied
across the joint seal 100 across the body top surface 114. Where
the coating 136, 504 provides fire resistance, the
elastically-compressible body 102 may be provided without a fire
retardant. The coating 136, 504 may further include an insulating
layer, such as a silicate, to add a refractory of insulating
function. However, such a layer, unless otherwise selected, would
not be a fire-retardant liquid glass formulation. The coating 136,
504 may include a flexible or semi-rigid elastomer to increase load
carrying capability which is further enhanced by the supporting
intumescent members. These, or other coatings, may be used to
provide waterproofing, fire resistance, or additional functional
benefits. Such coatings are known in the art, such as Dow 790.
The coating 136, 504 may undergo chemical reaction when heated to
reduce flammability or delay combustion or cool through physical
action or endothermic reactions. The coating 136, 504 may provide
retardancy through endothermic degradation, such as by use of
aluminum hydroxide. Coating 136, 504 may provide retardancy through
thermal shielding, such as by use of an intumescent, which chars
over when burned, separating the flame from the material and
slowing heat transfer. The coating 136, 504 may provide retardancy
by gas phase radical quenching, such as when chlorinated paraffin
undergoes thermal degradation and releases hydrogen chloride to
lower potential propagation of combustion reactions. The coating
136, 504 may extend down around the joint seal 100. In a further
alternative, the coating 136, 504 may an elastomeric gland.
When desired, the joint seal 100 may be structured to aid in
installation by beveling its bottom. The joint seal 100 may include
a body beveled surface 138 intermediate the body first side surface
104 and the bottom surface 140. Additionally or alternatively, the
joint seal 100 may further include one or more openings 142 at any
of the bottom surface 140, penetrating upward and becoming wider as
it penetrates further, such as by an initially rectangular prism
opening coupled with a cylindrical opening, which permits movement
and compression of the elastically-compressible body 102 but
limits, particularly at the bottom surface 140, the extent of such
movement. When desired, a structural member, such as a load
transfer member or an intumescent rod or other shape may be imposed
in each opening 142.
Further structural elements may be incorporated to increase the
fire resistance of the joint seal 100. Thus, the joint seal 100 may
include an intumescent member 164 in elastically-compressible body
102. Additionally, or alternatively, an intumescent body 168 may be
imposed within the elastically-compressible body 102 or in a
channel found on an exterior surface. The intumescent body 168 may
provide both fire retardancy and may extend beyond the joint seal
100 to overlap and join and adjacent joint seal 100.
Referring to FIG. 3, the elastically-compressible body 102 may
include, within and across its height or width a membrane 346. The
membrane 346 may be a vapor-impermeable layer. The membrane 346 may
provide a barrier to foreign matter penetrating through the joint
seal 100 and to opposing surface of the joint, thus ensuring some
portion of the core bodies are not susceptible to contaminants and
therefore continue to function. The membrane 346 may thus may
retain and then expel moisture, preventing moisture from
penetrating in an adjacent substrate. As can be appreciated, to be
effective, the membrane 346 is preferably sized to have a length at
least equivalent to the elastically-compressible body width 144,
the sum of body first side width 110 and the body second side width
112, into which it is placed, though it may be smaller or greater.
Alternatively, the membrane 346 may extend beyond the core bodies
to provide a surface which may contact an adjacent substrate and
even overlap its top. The membrane 346 may be intumescent or may
otherwise provide fire retardancy in the joint seal 100.
Referring to FIG. 4, the joint seal 100 may further include a
spring member 404, the spring member 404 presenting a wave-like
profile and having a spring member spring force positioned in the
elastically-compressible body 102. When desired, the spring member
404 may have an intumescent or fire retarding coating or
composition.
Finally, to ensure an anchor to the substrate, an adhesive may be
applied to the body first side surface 104. Moreover, an
intumescent rod 164 or other shape may be imposed within the joint
seal 100 and may also provide a key for splicing to an adjacent
joint seal 100. Beneficially, where the intumescent rod 164 extends
beyond a first end of the joint seal 100, it may be used to provide
a splice connection to an adjacent joint seal 100.
Referring to FIG. 9, other mechanical benefits can be incorporated
into the joint seal 100, such as a load transfer member 902
positioned on or below, i.e. adjacent, the body top surface 114 of
the 102 which distributes any load applied to the body top surface
114 of the elastically-compressible body 102 across a greater
surface area of the elastically-compressible body 102. The load
transfer member 902 may composed of any durable material, including
plastics, metals, or composites with its own spring force. The load
transfer member 902 may be provided with mechanical properties,
such as fire resistance, and may be intumescent.
Additionally, when desired, a sensor 904 may be included and may
contact one of more of the component of the joint seal 100. The
sensor 904 may be a radio frequency identification device RFID or
other wirelessly transmitting sensor. A sensor may be beneficial to
assess the health of a joint seal 100 without accessing the
interior of the expansion joint, otherwise accomplished by removal
of the cover plate. Such sensors are known in the art, and which
may provide identification of circumstances such as moisture
penetration and accumulation. The inclusion of a sensor 904 in the
joint seal 100 may be particularly advantageous in circumstances
where the joint seal 100 is concealed after installation,
particularly as moisture sources and penetration may not be
visually detected. Thus, by including a low cost,
moisture-activated or sensitive sensor, the user can scan the joint
seal 100 for any points of weakness due to water penetration. A
heat sensitive sensor may also be positioned within the joint seal
100, thus permitting identification of actual internal temperature,
or identification of temperature conditions requiring attention,
such as increased temperature due to the presence of fire, external
to the joint or even behind it, such as within a wall. Such data
may be particularly beneficial in roof and below grade
installations where water penetration is to be detected as soon as
possible.
Inclusion of a sensor 904 in the joint seal 100 may provide
substantial benefit for information feedback and potentially
activating alarms or other functions within the joint seal 100 or
external systems. Fires that start in curtain walls are
catastrophic. High and low-pressure changes have deleterious
effects on the long-term structure and the connecting features.
Providing real time feedback and potential for data collection from
sensors, particularly given the inexpensive cost of such sensors,
in those areas and particularly where the wind, rain and pressure
will have their greatest impact would provide benefit. While the
pressure on the wall is difficult to measure, for example, the
deflection in a pre-compressed sealant is quite rapid and linear.
Additionally, joint seals are used in interior structures including
but not limited to bio-safety and cleanrooms. Additionally, a
sensor 904 could be selected which would provide details pertinent
to the state of the Leadership in Energy and Environmental Design
LEED efficiency of the building. Additionally, such a sensor, which
could identify and transmit air pressure differential data, could
be used in connection with masonry wall designs that have cavity
walls or in the curtain wall application, where the air pressure
differential inside the cavity wall or behind the cavity wall is
critical to maintaining the function of the system. A sensor 904
may be positioned in other locations within the joint seal 100 to
provide beneficial data. A sensor 904 may be positioned to provide
prompt notice of detection of heat outside typical operating
parameters, so as to indicate potential fire or safety issues. Such
a positioning would be advantageous in horizontal of confined
areas. A sensor 904 so positioned might alternatively be selected
to provide moisture penetration data, beneficial in cases of
failure or conditions beyond design parameters. The sensor 904 may
provide data on moisture content, heat or temperature, moisture
penetration, and manufacturing details. A sensor 904 may provide
notice of exposure from the surface of the joint seal 100 most
distant from the base of the joint. A sensor 904 may further
provide real time data. Using a moisture sensitive sensor in the
joint seal 100 and at critical junctions/connections would allow
for active feedback on the waterproofing performance of the joint
seal 100. It can also allow for routine verification of the
watertightness with a hand-held sensor reader to find leaks before
the reach occupied space and to find the source of an existing
leak. Often water appears in a location much different than it
originates making it difficult to isolate the area causing the
leak. A positive reading from the sensor alerts the property owner
to the exact locations that have water penetration without or
before destructive means of finding the source. The use of a sensor
904 in the joint seal 100 is not limited to identifying water
intrusion but also fire, heat loss, air loss, break in joint
continuity and other functions that cannot be checked by
non-destructive means. Use of a sensor 904 within the joint seal
100 may provide a benefit over the prior art. Impregnated foam
materials, which may be used for the elastically-compressible body
102 are known to cure fastest at exposed surfaces, encapsulating
moisture remaining inside the elastically-compressible body 102,
and creating difficulties in permitting the removal of moisture
from within the elastically-compressible body 102. While heating is
a known method to addressing these differences in the natural rate
of cooling, it unfortunately may cause degradation of the foam in
response. Similarly, while forcing air through the
elastically-compressible body 102 may be used to address the curing
issues, the potential random cell size and structure impedes
airflow and impedes predictable results. Addressing the variation
in curing is desirable as variations affect quality and performance
properties. The use of a sensor 904 within the joint seal 100 may
permit use of the heating method while minimizing negative effects.
The data from the sensors, such as real-time feedback from the
heat, moisture and air pressure sensors, aids in production of a
consistent product. Moisture and heat sensitive sensors aid in
determining and/or maintaining optimal impregnation densities,
airflow properties of the foam during the curing cycle of the foam
impregnation. Placement of the sensors 904 into foam at the
pre-determined different levels allows for optimum curing allowing
for real time changes to temperature, speed and airflow resulting
in increased production rates, product quality and traceability of
the input variables to that are used to accommodate environmental
and raw material changes for each product lots.
The selection of components providing resiliency, compressibility,
water-resistance and fire resistance, the joint seal 100 may be
constructed to provide sufficient characteristics to obtain fire
certification under any of the many standards available. In the
United States, these include ASTM International's E 814 and its
parallel Underwriter Laboratories UL 1379 "Fire Tests of
Through-penetration Firestops," ASTM International's E1966 and its
parallel Underwriter Laboratories UL 2079 "Tests for
Fire-Resistance Joint Systems," ASTM International's E 2307
"Standard Test Method for Determining Fire Resistance of Perimeter
Fire Barrier Systems Using Intermediate-Scale, Multi-story Test
Apparatus, the tests known as ASTM E 84, UL 723 and NFPA 255
"Surface Burning Characteristics of Building Materials," ASTM E 90
"Standard Practice for Use of Sealants in Acoustical Applications,"
ASTM E 119 and its parallel UL 263 "Fire Tests of Building
Construction and Materials," ASTM E 136 "Behavior of Materials in a
Vertical Tube Furnace at 750.degree. C." Combustibility, ASTM E
1399 "Tests for Cyclic Movement of Joints," ASTM E 595 "Tests for
Outgassing in a Vacuum Environment," ASTM G 21 "Determining
Resistance of Synthetic Polymeric Materials to Fungi." Some of
these test standards are used in particular applications where
firestop is to be installed.
Most of these use the Cellulosic time/temperature curve, described
by the known equation T=20+345*LOG 8*t+1 where t is time, in
minutes, and T is temperature in degrees Celsius including E 814/UL
1379 and E 1966/UL 2079.
E 814/UL 1379 tests a fire-retardant system for fire exposure,
temperature change, and resilience and structural integrity after
fire exposure the latter is generally identified as "the Hose
Stream test". Fire exposure, resulting in an F [Time] rating,
identifies the time duration--rounded down to the last completed
hour, along the Cellulosic curve before flame penetrates through
the body of the system, provided the system also passes the hose
stream test. Common F ratings include 1, 2, 3 and 4 hours
Temperature change, resulting in a T [Time] rating, identifies the
time for the temperature of the unexposed surface of the system, or
any penetrating object, to rise 181.degree. C. above its initial
temperature, as measured at the beginning of the test. The rating
is intended to represent how long it will take before a combustible
item on the non-fireside will catch on fire from heat transfer. In
order for a system to obtain a UL 1379 listing, it must pass both
the fire endurance F rating and the Hose Stream test. The
temperature data is only relevant where building codes require the
T to equal the F-rating.
When required, the Hose Steam test is performed after the fire
exposure test is completed. In some tests, such as UL 2079, the
Hose Stream test is required with wall-to-wall and head-of-wall
joints, but not others. This test assesses structural stability
following fire exposure as fire exposure may affect air pressure
and debris striking the fire-resistant system. The Hose Stream uses
a stream of water. The stream is to be delivered through a 64 mm
hose and discharged through a National Standard playpipe of
corresponding size equipped with a 29 mm discharge tip of the
standard-taper, smooth-bore pattern without a shoulder at the
orifice consistent with a fixed set of requirements:
TABLE-US-00001 Hourly Fire Rating Water Pressure Duration of Hose
Time in Minutes kPa Stream Test sec./m.sup.2 240 .ltoreq. time <
480 310 32 120 .ltoreq. time < 240 210 16 90 .ltoreq. time <
120 210 9.7 time < 90 210 6.5
The nozzle orifice is to be 6.1 m from the center of the exposed
surface of the joint system if the nozzle is so located that, when
directed at the center, its axis is normal to the surface of the
joint system. If the nozzle is unable to be so located, it shall be
on a line deviating not more than 30.degree. from the line normal
to the center of the joint system. When so located its distance
from the center of the joint system is to be less than 6.1 m by an
amount equal to 305 mm for each 10.degree. of deviation from the
normal. Some test systems, including UL 1379 and UL 2079 also
provide for air leakage and water leakage tests, where the rating
is made in conjunction with a L and W standard. These further
ratings, while optional, are intended to better identify the
performance of the system under fire conditions.
When desired, the Air Leakage Test, which produces an L rating and
which represents the measure of air leakage through a system prior
to fire endurance testing, may be conducted. The L rating is not
pass/fail, but rather merely a system property. For Leakage Rating
test, air movement through the system at ambient temperature is
measured. A second measurement is made after the air temperature in
the chamber is increased so that it reaches 177.degree. C. within
15 minutes and 204.degree. C. within 30 minutes. When stabilized at
the prescribed air temperature of 204.+-.5.degree. C., the air flow
through the air flow metering system and the test pressure
difference are to be measured and recorded. The barometric
pressure, temperature and relative humidity of the supply air are
also measured and recorded. The air supply flow values are
corrected to standard temperature and pressure STP conditions for
calculation and reporting purposes. The air leakage through the
joint system at each temperature exposure is then expressed as the
difference between the total metered air flow and the extraneous
chamber leakage. The air leakage rate through the joint system is
the quotient of the air leakage divided by the overall length of
the joint system in the test assembly.
When desired, the Water Leakage Test produces a W pass-fail rating
and which represents an assessment of the watertightness of the
system, can be conducted. The test chamber for or the test consists
of a well-sealed vessel sufficient to maintain pressure with one
open side against which the system is sealed and wherein water can
be placed in the container. Since the system will be placed in the
test container, its width must be equal to or greater than the
exposed length of the system. For the test, the test fixture is
within a range of 10 to 32.degree. C. and chamber is sealed to the
test sample. Nonhardening mastic compounds, pressure-sensitive tape
or rubber gaskets with clamping devices may be used to seal the
water leakage test chamber to the test assembly. Thereafter, water,
with a permanent dye, is placed in the water leakage test chamber
sufficient to cover the systems to a minimum depth of 152 mm. The
top of the joint system is sealed by whatever means necessary when
the top of the joint system is immersed under water and to prevent
passage of water into the joint system. The minimum pressure within
the water leakage test chamber shall be 1.3 psi applied for a
minimum of 72 hours. The pressure head is measured at the
horizontal plane at the top of the water seal. When the test method
requires a pressure head greater than that provided by the water
inside the water leakage test chamber, the water leakage test
chamber is pressurized using pneumatic or hydrostatic pressure.
Below the system, a white indicating medium is placed immediately
below the system. The leakage of water through the system is
denoted by the presence of water or dye on the indicating media or
on the underside of the test sample. The system passes if the dyed
water does not contact the white medium or the underside of the
system during the 72-hour assessment.
Another frequently encountered classification is ASTM E-84 also
found as UL 723 and NFPA 255, Surface Burning Characteristics of
Burning Materials. A surface burn test identifies the flame spread
and smoke development within the classification system. The lower a
rating classification, the better fire protection afforded by the
system. These classifications are determined as follows:
TABLE-US-00002 Classification Flame Spread Smoke Development A 0-25
0-450 B 26-75 0-450 C 76-199 0-450
UL 2079, Tests for Fire Resistant of Building Joint Systems,
comprises a series of tests for assessment for fire resistive
building joint system that do not contain other unprotected
openings, such as windows and incorporates four different cycling
test standards, a fire endurance test for the system, the Hose
Stream test for certain systems and the optional air leakage and
water leakage tests. This standard is used to evaluate
floor-to-floor, floor-to-wall, wall-to-wall and top-of-wall
head-of-wall joints for fire-rated construction. As with ASTM
E-814, UL 2079 and E-1966 provide, in connection with the fire
endurance tests, use of the Cellulosic Curve. UL 2079/E-1966
provides for a rating to the assembly, rather than the convention F
and T ratings. Before being subject to the Fire Endurance Test, the
same as provided above, the system is subjected to its intended
range of movement, which may be none. These classifications
are:
TABLE-US-00003 Minimum Movement Minimum cycling Classification
number rate cycles Joint Type if used of cycles per minute if used
No Classification 0 0 Static Class I 500 1 Thermal
Expansion/Contraction Class II 500 10 Wind Sway Class III 100 30
Seismic 400 10 Combination
ASTM E 2307, Standard Test Method for Determining Fire Resistance
of Perimeter Fire Barrier Systems Using Intermediate-Scale,
Multi-story Test Apparatus, is intended to test for a systems
ability to impede vertical spread of fire from a floor of origin to
that above through the perimeter joint, the joint installed between
the exterior wall assembly and the floor assembly. A two-story test
structure is used wherein the perimeter joint and wall assembly are
exposed to an interior compartment fire and a flame plume from an
exterior burner. Test results are generated in F-rating and
T-rating. Cycling of the joint may be tested prior to the fire
endurance test and an Air Leakage test may also be
incorporated.
The joint seal 100 may therefore perform wherein the bottom surface
140 of the joint seal 100 at a maximum joint width increases no
more than 181.degree. C. after sixty minutes when the joint seal
100 is exposed to heating according to the equation T=20+345*LOG
8*t+1, where t may be time in minutes and T may be temperature in
C.
The joint seal 100 may also perform wherein the bottom surface 140
of the joint seal 100, having a maximum joint width of more than
six inches, increases no more than 139.degree. C. after sixty
minutes when the joint seal 100 is exposed to heating according to
the equation T=20+345*LOG 8*t+1, where t may be time in minutes and
T may be temperature in C.
The joint seal 100 may be adapted to be cycled one of 500 times at
1 cycle per minute, 500 times at 10 cycles per minute and 100
cycles at 30 times per minute, without indication of stress,
deformation or fatigue.
In other embodiments, the joint seal 100 is configured to pass
hurricane force testing to TAS 202/203. Further the joint seal 100
may be designed or configured to pass ASTM E-282, E-331, E-330,
E-547 or similar testing to meet the pressure cycling and water
resistance requirements up to 5000 Pa or more.
The present disclosure thus provides a dimensional stability, as a
result of the reduction of main foam, while requiring less silicone
as the elastically-compressible body width 144, defining the size
of the top to be coated, is less than that of the convention joint.
Additionally, no fixture is required for anchorage. In operation,
less strain is imparted to the foam of the main body, while a
higher compression is generated, resulting in a tighter seal.
Additionally, at the top and bottom of the main body, less strain
is introduced in light of the lack of the secondary bodies at those
positions. The construction of the present invention further
results in the top and bottom being pulled inward against any
bowing. This construction results in better recovery as areas of
lower compression expand faster than those under higher
compression.
Beneficially, the joint seal 100 of the present invention may be
horizontally or vertically aligned or in combination and may be
used to limit the level of moisture or air penetration to a certain
level or area while substantially blocking the moisture or air in a
specific region at the surface. The joint seal 100 may also perform
symmetrically or asymmetrically based on assembly and material
choices. Compared to conventional joint seals, the present joint
seal 100 may have a reduced density, a reduced weight when
installed, reduced volume of filler or binder, and compression
required to function.
The foregoing disclosure and description is illustrative and
explanatory thereof. Various changes in the details of the
illustrated construction may be made within the scope of the
appended claims without departing from the spirit of the invention.
The present invention should only be limited by the following
claims and their legal equivalents.
* * * * *